Comey "let the country down for partisan purposes," Reid said, calling him "the new J. Edgar Hoover," a reference to the powerful long-time FBI director (1935-1972) who carried out domestic espionage against political dissidents and collected secret files of dirty secrets about political leaders.

Republicans on Saturday rejected news reports about a secret CIA assessment finding that Russia sought to tip the US election in Trump's favor.

The New York Times reported that US intelligence agencies had "high confidence" that Russian hackers infiltrated the Republican National Committee's computer systems as well as Democratic Party's, but released information taken only from Democratic computers.

President Barack Obama has ordered a review of all cyberattacks that took place during the 2016 election cycle, the White House said Friday.

Reid's successor as the top Senate Democrat, Chuck Schumer, also called for a congressional investigation into the matter on Saturday.